Tuesday, October 27, 2015

Impact of Chicago Marathon on the Cutoff Prediction

I think we are starting to see enough critical mass of qualifier data that the change of the cutoff prediction from race to race will be less volatile.

As you may or may not have heard, the weather at Chicago this year was sub-optimal. Mid 70s at the finish for most folks (it was 75F when I finished with 3:46 and I was only about 6 or 7 minutes behind the official start in Corral C). According to this website the race start conditions in 2014 were partly cloudy and 46F, with a high of 64F. 2015 it was 54F and clear with a high of 78F. However the rate of BQ year over year for that race was only 0.09% lower.

Anyway, onto the numbers.

AG

2014 Qualifiers

2014 AG Total

% Qualifiers

2015 Qualifiers

2015 AG Total

% Qualifiers

F18-34

1192

13979

8.53%

1094

12619

8.67%

F35-39

561

4956

11.32%

530

4753

11.15%

F40-44

476

4286

11.11%

444

3917

11.34%

F45-49

434

2763

15.71%

432

2824

15.30%

F50-54

241

1729

13.94%

270

1784

15.13%

F55-59

132

910

14.51%

112

824

13.59%

F60-64

63

365

17.26%

59

377

15.65%

F65-69

20

120

16.67%

25

133

18.80%

F70-74

5

34

14.71%

3

35

8.57%

F75-79

0

10

0.00%

1

7

14.29%

F80+

0

0

0.00%

0

1

0.00%

M18-34

1024

11885

8.62%

881

10597

8.31%

M35-39

487

5549

8.78%

474

5159

9.19%

M40-44

538

5484

9.81%

489

5051

9.68%

M45-49

608

4283

14.20%

542

4100

13.22%

M50-54

488

3275

14.90%

419

3102

13.51%

M55-59

309

2091

14.78%

269

2008

13.40%

M60-64

179

1041

17.20%

158

1018

15.52%

M65-59

45

273

16.48%

37

273

13.55%

M65-69

32

143

22.38%

28

129

21.71%

M70-74

30

157

19.11%

18

146

12.33%

M75-79

5

44

11.36%

8

40

20.00%

M80+

0

8

0.00%

2

13

15.38%

Totals

6869

63385

10.84%

6295

58910

10.69%

The numbers have stayed similar with the inclusion of Chicago. Even though the rate of BQ 2014 to 2015 was about the same (less than .1% difference), there were fewer qualifiers. This will have downward pressure on the 2017 cutoff.

Here is the margin breakdown:

Margin

2014

Percentage

2015

Percentage

<1 minute

411

5.98%

344

5.46%

1-2 minutes

415

6.04%

332

5.27%

2-3 minutes

379

5.52%

322

5.12%

3-4 minutes

345

5.02%

325

5.16%

4-5 minutes

314

4.57%

259

4.11%

5-10 minutes

1433

20.86%

1290

20.49%

10-20 minutes

1791

26.07%

1722

27.36%

20> minutes

1781

25.93%

1701

27.02%

Totals

6869

6295

Nothing new, the Squeaker Pack in 2015 has shrunk from 27.14% to 25.13% with the biggest gains in the 10+ minutes of margin.

The total number of runners in the 5 races analyzed with 147 seconds (or 2:28) of qualification margin in 2014 was 5658.

Sorting by margin in seconds descending, the 5658th runner in the five 2015 races analyzed as a margin of...

5 comments:

Thank you for doing this! I have been trying to BQ for years and finally did with a 2:20 margin. Although I know anything can happen, your analysis gives me hope that I might find myself at the starting line in 2017!

I agree the swings will be less volatile, at least until Boston. Ultimately, I think the entire analysis hinges on Boston as it did this past year. If there is good weather there, the cutoff swings dramatically (far more so than any other race and even accounting for the raw # of qualifiers). We'll see...

Thanks for doing this! I'll be following this blog this year, much like how I followed Boston Qualifier Stats' blog last year.

One comment about the first table: I think the numbers for the men in the 2014 columns have been shifted one row upward (I don't believe there were more than 11 thousand women 80 years or older who ran Chicago last year).